Concentrating-jig



GVGLOCKEMEIER.

CONCENTRATING HG.

APPLICATION FILED JUNE 28, 1919.

1,354,55 Patented Oct. 5,1920.

6. GlocKem eier Attorney UNlTED STATES PATENT OFFICE.

GEORG GLOCKEMEIEB, OF LUDERITZBUOI-ZT, SOUTI-i VVES'II PROTECTORATE,SOUTH AFRICA, ASSIGNOR T0 CARL KEAUSE, OF LUDERITZBUGHT, SOUTH WEST PRO-TECTORATE, SOUTH AFRICA.

CONGENTRATING-JIG.

Specification of Letters Patent.

Patented Oct. 5, 1920.

Application filed June 28, 1919. Serial lilo. 307,448.

T 0 all whom it may concern:

it known that 1, Gross Gnocnnnrninn, citizen of South Vi estProtectorate, South tries, residing at Luderitzbucht, South estirotectorate, South 3* Tim, have inccrtain new and useful Improve antsin Concentrating igs, of which the tolii 4 specification.

The oresent invention relates to jig concentrating apparatus forrecovering diamonds and other precious stones and ore concentrates; saidapparatus being of the id in which relative vertical reciprocationbrought about between a bed of the material carried on a sieve and abody of water in which it is immersed.

The present invention is based on the discovery that when the jig screenis curved or inclined the concentrate tends to rise to the highest pointof the screen instead of passir to the lowest point as has hitherto beeniought. This phenomenon can be explained the fact that the shape of thesieve causes 1 bed radually to decrease in thickthe higher part of thescreen. The wa er acting upwardly on the bed, finds t r sistance towardsuch thin part of the c. stream of water, which is origially perfectlyvertical, is thus diverted tothe highest point of the screen and theconcentrates,being the heaviest particles, and therefore lyinimmediately on the screen,are pushed rorward in the direction of thehighest point.

The present invention accordingly consists in the method of forming ajig bedof gradually varying thickness and discharging the concentrate ator near the thinnest point or Zone of the bed. N The invention alsoconsists in a jig having an inclined or curved screen, in which themeans for feeding the jig material and the discharge orifices for theconcentrates are disposed to take advantage of this rising tendency ofthe concentrate. The invention also consists in the specific forms ofsieve herea fter described.

In the accompanying drawings Figure I is a vertical section of a jig ofthe Schiechel type embodying the invention.

Fig. IT is a plan of the screen drawn to a larger scale.

Figs. Hi and IV are sectional elevations taken at right angles to oneanother of a rectangular screen suitable for a Hartz Referring first toFigs. I and ll, 1 is the screen mounted on a frame 2 and supported indome form by ribbing 3, 3

The sieve is carried at the top of a chamber i communicating with anannular cham- 5 closed at the top. Said chambers 4 and 5 contain waterto about the level of the sieve; and pulsation of the water in chamber iis brougnt about by pulsations of the air toe ieed possible with therising movement of the concentrate. Accordingly the feed spout 10 isarranged to deliver the material onto a restricted area at the center ofthe sieve. The discharge holes are arranged, as appears in Fig. ii, in acircle at such a distance from the center that the pressure of the feedceases materially to interfere with the climbing tendency of theconcentrate.

The supporting frame on which the sieve mesh rests is arranged tointerfere as little as possible with the direct action of the water onthe jig bed. The members 3 of the supporting ribbing are radial; andwhere an annular nember 3 is employed it is placed within the Zone ofthe discharge openings 8. This feature is of importance in thesuccessful operation of the sieve since the proper movement concentratelying on the sieve depends upon the direct pressure of water upon it. Itfor instance the annular member 3 were placed outside the ring of holes8, it would form a barrier past which the concen- 'trate could be movedonly with great difiipulsations of the water or the sieve frame.

It was believed that the concentrates went to the center of thestretched sieve because this was the deepest point in the suction phase.

While therefore the discharge orifice was positioned in'the center, thejig material was fed to an annular zone half way between the edge of thesieve and the center. The result was that the fresh material formed abarrier which the concentrates could only pass with difliculty on theirway to the discharge. The output of such a sieve is materially increasedby modifying it in accordance with this invention.

Figs. HI and IV illustrate an application of the invention to a sievefor a jig of the Hart'z type in which the sieve is rectangular, the jigmaterial being fed at one end 11 and the 't'ailings being discharged atthe other end 12.

In this case the sieve is curved or inclined upwardly from both sides tothe middle longitudinal line 13. The supporting ribs 3 are arrangedtransversely to the length of the sieve. Concentrates mount to thecentral ridge of the sieve and are carried by the general longitudinalmovement ofthe whole material to the concentrate discharge spout 14;, 15which is situated on the central line and near the discharge end 12. Thedischarge spout consists of a fixed tube 14 and a tube 15' revolubletherein. Said tubes are formed with corresponding apertures 16, throughwhich the concentrate passes away. By rotating the tube 15 the size ofthe discharge opening can be regulated.

I claim a 1. A jig sieve having sloping sides and a raised centralportion provided withconcentrate discharge openings in proximity to itshighest point.

2. In a jig, an upwardly domed sieve having concentrate dischargeopenings in an annular zone near to the center, and a feed devicearranged to feed jig material to a restricted area in the center of thesieve.

3. A rigid jig sieve including a convex screen body having a circle ofconcentrate discharge openings near the center, a supporting rim at theouter edge of the screen body, a reinforcing ring secured to the screenbody and positioned Within the circle of openings and radial ribsbetween the ring and the rim.

In testimony whereof I affix my signature.

GEORG GLOCKEMEIER.

